This invention relates to a door locking mechanism and more particularly to a door locking mechanism for mounting on the inside of a door which is capable of being locked in either the open or closed position.
Commercial establishments, especially where large numbers of persons may congregate, usually must be provided with outswinging exit doors to facilitate the egress of persons during a fire or other emergency. Quite often, these doors are provided with burglar bars to prevent unauthorized entry from the outside when the premises are vacant. Thus, the bar must be removed in accordance with fire regulations when the premises are in use and put back in place at other times. In such an arrangement the bar must be stored when not in use, and can be misplaced, lost, or even stolen in some cases.
A variety of burglar bar arrangements are shown in various United States Patents.
U.S. Pat. No. 3,819,216 to Richardson shows a burglar bar of the type which must be removed to use the door. In U.S. Pat. No. 3,908,328 to Pearson, there is a bar attached to the door opening rather than the door itself and is designed to secure the door knob. U.S. Pat. No. 4,270,311 to Palomar discloses an escape hatch with a pair of latch assemblies at opposite ends of the latch. U.S. Pat. No. 4,529,235 to Florentine has a door bolting device designed for use with a door shut for a prolonged period.
All of the patent devices described above are awkward to use, complex in construction, or are otherwise unsatisfactory for use under the conditions described.